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> Fuel pressure and spark but won't run
Groosh
post Oct 23 2016, 03:50 PM
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QUOTE(timothy_nd28 @ Oct 23 2016, 01:11 PM) *

Yah, time to replace them.

Happened to have a set at home. So I replaced and set the gap. I tried turning it over but still no love.
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timothy_nd28
post Oct 23 2016, 06:12 PM
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On the ignition coil, you should have 3 wires on the negative terminal and one wire on the positive terminal. After confirming that, remove all wires from the ignition coil and check the resistance between the positive and negative terminal of the ignition coil. Next, leave one meter lead probed to the negative terminal and probe the other meter lead to the spark plug socket of the ignition coil.
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Groosh
post Oct 24 2016, 03:05 PM
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QUOTE(timothy_nd28 @ Oct 23 2016, 04:12 PM) *

On the ignition coil, you should have 3 wires on the negative terminal and one wire on the positive terminal. After confirming that, remove all wires from the ignition coil and check the resistance between the positive and negative terminal of the ignition coil. Next, leave one meter lead probed to the negative terminal and probe the other meter lead to the spark plug socket of the ignition coil.


Yes, three wires on the negative. The postive has two wires tied together on it.

Probed the coil negative and positive and got 0 ohms resistance.

Probed the negative and positive at the spark plug socket and got 100 ohms resistance with meter set at RX100.
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timothy_nd28
post Oct 24 2016, 04:58 PM
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Just to make sure, did you pull all the wires off before testing? Positive to negative terminals should be around 4 ohms. Spark plug terminal to either terminal should be around 10,000 ohms.
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Groosh
post Oct 24 2016, 05:12 PM
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QUOTE(timothy_nd28 @ Oct 24 2016, 02:58 PM) *

Just to make sure, did you pull all the wires off before testing? Positive to negative terminals should be around 4 ohms. Spark plug terminal to either terminal should be around 10,000 ohms.


Yes, the wires were pulled. However I retested. This time I used a digital meter and found 4 ohms and about 9,470 ohms from the spark plug terminal.
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timothy_nd28
post Oct 24 2016, 08:07 PM
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That indicates that the coil is good. So, you have 12 volts on the + ignition coil terminal when the key is on, and a new set of points, but no spark.

Sounds like a grounding issue. Check the transmission ground strap
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timothy_nd28
post Oct 24 2016, 10:55 PM
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After checking the ground strap, take your voltmeter and check the resistance between the negative battery post and the thing I have circled in red, you should have 0 ohms

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Groosh
post Oct 25 2016, 02:00 PM
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QUOTE(timothy_nd28 @ Oct 24 2016, 08:55 PM) *

After checking the ground strap, take your voltmeter and check the resistance between the negative battery post and the thing I have circled in red, you should have 0 ohms

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The ground strap from tranny to car looks good. Quite clean. There is also an extra ground cable from the negative battery terminal to the transmission.

The volt meter at the points think circled in red reads 0 ohms.
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timothy_nd28
post Oct 25 2016, 02:17 PM
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Reattach wires to the ignition coil. Turn the engine so that the ignition points are in the closed position. Check the resistance from the negative terminal of the ignition coil to the negative battery post. You should again see 0 ohms.

If you see 0 ohms, switch the meter to measure DC volts. Briefly turn the key to on and measure the voltage between the + and - terminals of the ignition coil. You should see 12 volts. Turn off the ignition as soon as you get your measurement.
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Groosh
post Oct 25 2016, 02:48 PM
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QUOTE(timothy_nd28 @ Oct 25 2016, 12:17 PM) *

Reattach wires to the ignition coil. Turn the engine so that the ignition points are in the closed position. Check the resistance from the negative terminal of the ignition coil to the negative battery post. You should again see 0 ohms.



If you see 0 ohms, switch the meter to measure DC volts. Briefly turn the key to on and measure the voltage between the + and - terminals of the ignition coil. You should see 12 volts. Turn off the ignition as soon as you get your measurement.


On this, my ohms meter did not go to 0.

I tried this measure too and did not get 12 volts. I did get any volts reading.

The key is off.
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timothy_nd28
post Oct 25 2016, 02:52 PM
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Silly question, but are the points in the closed position (touching each other) when you measured?
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Groosh
post Oct 25 2016, 03:24 PM
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QUOTE(timothy_nd28 @ Oct 25 2016, 12:52 PM) *

Silly question, but are the points in the closed position (touching each other) when you measured?


Yes. Were they supposed to be?
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timothy_nd28
post Oct 25 2016, 04:10 PM
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Yes. Now check the resistance between the negative terminal of the ignition coil to the points that I circled in red.
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Groosh
post Oct 25 2016, 04:32 PM
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QUOTE(timothy_nd28 @ Oct 25 2016, 02:10 PM) *

Yes. Now check the resistance between the negative terminal of the ignition coil to the points that I circled in red.


Key off, points closed. 0 ohms.

I noticed I kicked off a wire accidentally from the negative coil. I redid the test of resistance from negative coil to negative battery and got 0 ohms.

I tried the test from neg coil to pos coil for DC V and did not get anything. I think...
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timothy_nd28
post Oct 25 2016, 04:57 PM
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That's fine, thanks for telling me. Repeat the test from post# 56.

You have a solid ground at the negative terminal at the ignition coil, and if the results from post 56 gives you a green light, by definition you should have 12 volts between the positive and negative terminal at the ignition coil.
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Groosh
post Oct 25 2016, 05:01 PM
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QUOTE(timothy_nd28 @ Oct 25 2016, 02:57 PM) *

That's fine, thanks for telling me. Repeat the test from post# 56.

You have a solid ground at the negative terminal at the ignition coil, and if the results from post 56 gives you a green light, by definition you should have 12 volts between the positive and negative terminal at the ignition coil.


Yes. There are 12 volts at the positive coil metered to negative battery terminal.
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timothy_nd28
post Oct 25 2016, 06:19 PM
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Redo the test from the 2nd paragraph from post #69
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Groosh
post Oct 26 2016, 04:29 PM
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So I've been working with Tim and he has been absolutely invaluable in helping me to diagnose and repair this wiring train wreck. Thank you to Tim and the 914World forum!

To help close the loop for others reading this post we, and by we I mean Tim, finally figured out that the condensor was shorting out. By cutting the wire to it we returned spark to the engine and it fired. The engine doesn't quite run but we are getting closer.
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Frankvw
post Oct 26 2016, 11:18 PM
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That is good to hear. Thanks for the update. Interesting post for sure!
good luck with the final steps and keep us updated. I understand the issue is a pita for you, but by posting this others learn from it.
thanks Groosh and Tim.
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Groosh
post Feb 24 2017, 11:17 AM
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Since it's 60 degrees in Michigan, I've attempted some updating on the car. I went to electronic ignition by Hot Spark and the car fired up. But as I was adjusting the timing and revving it, the car died.

It looks like the fuel pump stopped working. There was no pressure to the rail when I cranked. But then I tried to jumped the relay to get the fuel pump going and still the car doesn't run.

Harumph. I thought I had this thing ready.
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